surgical outcomes of membrane-tube-type glaucoma shunt ...university of ibadan/university college...
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Clinical Ophthalmology 2018:12 279–286
Clinical Ophthalmology Dovepress
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open access to scientific and medical research
Open access Full Text article
http://dx.doi.org/10.2147/OPTH.S148325
surgical outcomes of membrane-tube-type glaucoma shunt device in indigenous West africans
Olusola Olawoye1,2
Tarela sarimiye1,2
adeyinka ashaye1,2
Young hoon hwang3
Jong Chul han4
Byung heon ahn3
1Department of Ophthalmology, College of Medicine, University of ibadan, 2Department of Ophthalmology, University College hospital, ibadan, nigeria; 3Department of Ophthalmology, Konyang University, Kim’s eye hospital, Myung-gok eye research institute, 4Department of Ophthalmology, samsung Medical Center, sungkyunkwan University, school of Medicine, seoul, south Korea
Purpose: The aim of this study was to report the safety and efficacy of the membrane-tube
(MT)-type glaucoma shunt device (Finetube MT) in the management of refractory glaucoma
in indigenous West Africans.
Methods: The Finetube MT was implanted into 25 eyes of 25 West African patients with
refractory glaucoma. These patients had inadequate intraocular pressure (IOP) control despite
maximum tolerable IOP-lowering medications with or without previous ocular surgeries. IOP,
postoperative complications, interventions, visual acuities, and the number of IOP-lowering
medications were analyzed preoperatively and postoperatively.
Results: The mean (standard deviation [SD]) age of the patients was 49.7 (20.9) years. The
mean (SD) follow-up duration was 21.0 (10.6) months. Postoperatively, the mean (SD) IOP
reduced from a preoperative value of 38.1 (10.3) mmHg to 14.5 (4.6), 16.1 (7.8), and 14.7
(3.0) mmHg at 1, 2, and 3 years postoperatively, respectively, representing 61.9%, 57.7%, and
61.4% reduction from baseline (P,0.01). The mean (SD) number of IOP-lowering medica-
tions reduced from 4.1 (1.0) to 0.6 (0.9) at 1 year and 0.9 (1.1) at 2 years after the operation
(P,0.01). Using an IOP level between 6 and 21 mmHg and reduced by $20% from baseline,
the cumulative survival rate (standard error) was 96.0% (3.9%) at 6 months, 89.0% (6.0%) at
18 months, and 81.3% (10.6%) at 3 years after the operation. There was no postoperative ocular
hypotony, tube occlusion, or device exposure.
Conclusion: The Finetube MT may effectively control IOP with minimal risk of postoperative
complications in indigenous West Africans.
Keywords: glaucoma, intraocular pressure, glaucoma shunt device, West Africa
IntroductionGlaucoma has a huge health burden in sub-Saharan Africa (SSA).1 The African region
has the highest incidence and prevalence of glaucoma, and it is disproportionately
affected by blindness.2 Glaucoma accounts for 15% of blindness in SSA compared
to 8% in the world.1 A recent study done in Nigeria reported that approximately one
in every five patients with primary glaucoma was blind.3 Reported prevalence of
glaucoma in population-based studies within SSA ranges from 5.3% among South
African blacks4 to as high as 6.9% in South West Nigeria.5 Budenz et al6 reported a
prevalence of glaucoma as high as 17.8% among males aged between 70 and 79 years
and 20.1% among those older than 80 years in Ghana, West Africa.
Currently, lowering intraocular pressure (IOP) is the most effective way to prevent
development and progression of glaucoma. Glaucoma can either be treated medically,
surgically, or with the use of lasers. The cost of medical treatment in much of SSA
is high and oftentimes unaffordable. This is further complicated with the problem
of poor compliance and unavailability of medications in these resource-constrained
Correspondence: Olusola OlawoyeDepartment of Ophthalmology, College of Medicine, University of ibadan, ibadan 20004, nigeriaTel +234 80 2389 0063email [email protected]
Journal name: Clinical OphthalmologyArticle Designation: Original ResearchYear: 2018Volume: 12Running head verso: Olawoye et alRunning head recto: Glaucoma shunt device in West AfricansDOI: http://dx.doi.org/10.2147/OPTH.S148325
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Olawoye et al
regions. In a study done in South West Nigeria, only 27.2%
of glaucoma patients self-reported 100% adherence with their
medication within the study period.7
Although trabeculectomy has been advocated as the first
line of the surgical management for primary open-angle
glaucoma in SSA, studies show that the failure rate is higher
in Africans compared to Caucasians.8–10 Moreover, Africans
are more likely to require surgical interventions after trab-
eculectomy compared with Caucasians because Africans
have a greater concentration of conjunctival fibroblasts and
macrophages, suggesting a more aggressive wound healing
process.11 In addition, the acceptability of the procedure is
reported to be as low as 8%.12 Many surgeons in SSA are
reluctant to perform trabeculectomy because of the uncertain
outcomes,13 especially in the early postoperative period when
sudden high or low IOP can lead to visual impairment.
Implantation of a glaucoma drainage device (GDD) is a
useful surgical option in refractory glaucoma. Surveys have
demonstrated an increase in the popularity of GDDs as an
alternative to trabeculectomy, especially in eyes that have
undergone previous ocular surgery.14,15 Previous studies done
in SSA have demonstrated the efficacy of GDDs in indigenous
Africans.16–18 However, these devices are relatively expensive
to the much of patients in SAA and therefore not readily avail-
able. Thus, we have tried to develop a novel GDD with a lower
price and similar or better surgical outcomes compared to
conventional GDDs.19,20 A newly developed membrane-tube
(MT)-type glaucoma shunt device (Finetube MT) designed
by the authors drains aqueous humor from the anterior
chamber to the post-equatorial sub-Tenon’s space, similar to
conventional GDDs, such as Ahmed glaucoma valve (AGV;
New World Medical, Rancho Cucamonga, CA, USA) and
the Baerveldt glaucoma implant (BGI; Abbott Laboratories,
Abbott Park, IL, USA). According to our previous study, the
Finetube MT showed safe and effective IOP control in Korean
patients.20 We thought that Finetube MT may also be useful
for the IOP control in indigenous West Africans.
The aim of this study was to evaluate the safety and
efficacy of the Finetube MT in treating refractory glaucoma
in indigenous West Africans. These preliminary data pro-
vides information on the surgical outcomes of this device
in this population and forms the basis for future prospective
studies on the use of GDDs in the surgical management of
glaucoma in SSA.
MethodsThis study is a retrospective, non-comparative, non-
randomized, interventional case series. The study conformed
to the tenets of the Declaration of Helsinki, and all
patients gave informed written consent. Ethical approval
was obtained from the institutional review board of the
University of Ibadan/University College Hospital, Ibadan.
Patients enrolled were those who underwent Finetube MT
implantation between March 2013 and April 2016 and those
with a minimum follow-up period of 6 months. All eligible
patients had glaucoma with inadequate IOP control despite
maximum tolerable medical therapy with or without previ-
ous trabeculectomy. Patients with secondary glaucoma, such
as neovascular glaucoma, uveitic glaucoma, or traumatic
glaucoma, in whom poor outcome was expected with trab-
eculectomy were indicated for the Finetube MT implantation
as the first-line surgical treatment.
All patients underwent comprehensive eye examination
that consisted of best-corrected visual acuity test, slit-lamp
examination, IOP measurement by Goldmann applanation
tonometry, and gonioscopy using a 4-mirror Posner lens.
Automated full-threshold visual fields test was performed
for patients with best-corrected visual acuity better than 6/60
using the 24-2 Swedish Interactive Threshold Algorithm stan-
dard program on the Humphrey 740 Visual Field Analyzer
(Carl Zeiss Meditec AG, Jena, Germany). Pupils were dilated,
and stereoscopic examination of the vitreous, retina, and optic
nerve head was done with the 78-diopter lens.
Profile of the Finetube MT has been described in detail in
an earlier study.20 In brief, it consists of an aqueous reservoir
membrane with a surface area of ~180 mm2 and a silicone
tube with a 300 μm external diameter and a 200 μm internal
diameter with an intraluminal stent of 5-0 nylon thread
(Figure 1A). The tube induces aqueous drainage from the
anterior chamber to the membrane, and the intraluminal
stent prevents excessive aqueous drainage through the tube
and enables additional aqueous drainage after the surgery
by retracting it.19,20
surgical techniqueAll surgeries were done by one surgeon (OO). The proce-
dure for the Finetube MT implantation has been presented
in detail in an earlier study.20 Briefly, this involved creat-
ing a parallel conjunctival incision 8–10 mm away from
the limbus superotemporally. The superior and lateral recti
muscles were identified with a squint hook. The membrane
reservoir was then inserted underneath the Tenon’s cap-
sule, and the wings of the membrane were inserted under
the two recti muscles. The anterior aspect of the membrane
was sutured to sclera with 9-0 nylon (Figure 1B). A second
perpendicular conjunctival incision was made ~2–3 mm away
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glaucoma shunt device in West africans
from the superotemporal aspect of the limbus. By using a
23-gage needle, a partially thick scleral tunnel of ~1 mm
length was made and a track was made within sclera to
the forniceal wound (Figure 1C). The tube tip was then
inserted into the lumen of 23-gage needle; the needle was
retracted such that the tube was passed into the partially
thick scleral tunnel (Figure 1D). The tube was cut beveled
up such that ~2 mm of the tube was placed into the anterior
chamber. A track was then made into the anterior chamber
from the perilimbal scleral track using a 26-gage needle,
and the silicone tube was inserted into the anterior chamber
(Figure 1E). The scleral track, conjunctiva, and Tenon’s
capsule were closed with 10-0 nylon sutures. The 5-0 nylon
stent was left partially exposed through conjunctiva such
that it can be pulled out after the operation when further IOP
reduction is necessary (Figure 1F). At the end of operation,
subconjunctival injections of dexamethasone and gentamicin
were given. After surgery, patients were placed on topical
antibiotics of moxifloxacin hydrochloride 0.5% solution
(Vigamox; Alcon Laboratories, Inc., Fort Worth, TX, USA)
and dexamethasone ophthalmic suspension (Maxidex 0.1%;
Alcon Laboratories, Inc.) 2 hours for 2 weeks and then four
times for another 4 weeks.
When postoperative IOP did not reach the desired level
(IOP ,21 mmHg and $20% reduction from baseline),
we gently retracted the intraluminal stent partially using
forceps under the slit lamp biomicroscope in the outpatient
clinic. After removing the stent, IOP was measured again
1 hour later. If the IOP was still unsatisfactory despite
partial removal of the stent, the whole stent was removed.
Figure 1 surgical technique of MT-type glaucoma shunt device (Finetube MT) implantation.Notes: The Finetube MT consists of a aqueous reservoir membrane with a surface area of ~180 mm2 and a silicone tube with a 300 μm external diameter and a 200 μm internal diameter with an intraluminal stent of 5-0 nylon thread (A). Conjunctival incision was made 8–10 mm away from the limbus superotemporally. The membrane reservoir was then inserted underneath the Tenon’s capsule and the anterior aspect of the membrane was sutured to sclera (B). a second conjunctival incision was made ~2–3 mm away from the superotemporal aspect of the limbus. By using a 23-gage needle, a track was made within the sclera to the forniceal wound (C). The tube tip was then inserted into the lumen of 23-gage needle; the needle was retracted such that the tube was passed into the partially thick scleral tunnel (D). a track was then made into the anterior chamber from the perilimbal scleral track using a 26-gage needle, and the silicone tube was inserted into the anterior chamber (E). The scleral track, conjunctiva, and Tenon’s capsule were closed with 10-0 nylon sutures. The 5-0 nylon stent was left partially exposed through conjunctiva such that it can be pulled out after the operation when further iOP reduction is necessary (F).Abbreviations: MT, membrane tube; iOP, intraocular pressure.
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Olawoye et al
Independent of the IOP, the stent was removed in all cases
at 4 weeks after the operation when the flow restriction by
the stent was no longer needed; by this time, there will be
wound healing around the plate and it may reduce the risk
of ocular hypotony.19,20
Data collection and statistical analysisPreoperative data collected were patient’s age, sex, diagnosis,
IOP, best-corrected visual acuity, optic disk findings, mean
deviation value of visual field test, and number of IOP-
lowering medications. Postoperative IOP within 48 hours;
at 1 month, 3 months, 6 months, 1 year, and 2 years; and
at the last visit were collected. Other data, such as the
postoperative best-corrected visual acuity and number of
IOP-lowering medications, were also collected. We analyzed
changes in postoperative IOP, visual acuity, and number of
IOP-lowering medications compared with baseline status by
using Wilcoxon signed-rank test.
We defined surgical success based on the consensus on
surgical outcome by the World Glaucoma Association.21
Complete success was defined as an IOP of #21, #18,
and #15 mmHg without the use of IOP-lowering medications
following the operation, and qualified success was defined as
an IOP of #21, #18, and #15 mmHg with or without the
use of IOP-lowering medications after the surgery. In order to
compare our study results with previously done similar study
results,20 we also considered success as an IOP between 6 and
21 mmHg and reduced by $20% from baseline, with or with-
out the use of IOP-lowering medications. Patients with IOP
,6 mmHg or IOP .21 mmHg on two consecutive follow-up
visits or requiring additional glaucoma surgery to control IOP
were considered failures. These criteria were used for the cal-
culation of cumulative survival rate by using Kaplan–Meier
survival analysis. We defined postoperative ocular hypotony
as an IOP ,6 mmHg. Data were collated and analyzed using
the IBM Statistical Package for the Social Sciences (SPSS)
software version 21 (IBM Corporation, Armonk, NY, USA).
The significance level was set at P,0.05.
ResultsA total of 25 eyes of 25 patients were enrolled. The clinical
characteristics of the patients are presented in Table 1. The
mean (standard deviation [SD]) age was 49.7 (20.9) years and
males accounted for 16 (64%) patients. The mean follow-up
period was 21.0 (10.6) months with a range of 6–36 months.
Failed trabeculectomy was the most common indication
for Finetube MT surgery accounting for 10 (40%) patients.
The mean (SD) preoperative IOP was 38.1 (10.3) mmHg
(range, 22–62 mmHg). The mean number of preoperative
IOP-lowering medication was 4.1 (1.0; range, 2–5). All the
eyes showed nearly total cupping of optic disk and mean
deviation of visual field test worse than -30 dB.
After the Finetube MT implantation, the mean IOP
reduced to 10.9 (6.7), 14.2 (5.3), 14.7 (5.1), 14.5 (4.6),
16.1 (7.8), and 14.7 (3.0) mmHg at postoperative first day,
1 month, 6 months, 1 year, 2 years, and 3 years, respec-
tively, representing 71.4%, 62.7%, 61.4%, 61.9%, 57.7%,
and 61.4% reduction from baseline (P,0.01; Figure 2).
Table 1 Clinical characteristics of patients before the MT-type glaucoma shunt device implantation
Characteristics Values
age (years)sex, n (%)
MaleFemale
49.7 (20.9)
16 (64)9 (36)
Previous ocular surgery, n (%)TrabeculectomyCataract surgeryintravitreal injectionsnone
10 (40)9 (36)3 (12)3 (12)
Diagnosis, n (%)POag with failed trabeculectomyPOag with pseudophakiaPOag without previous surgeryUveitic glaucomaneovascular glaucomaChronic angle closure glaucomasteroid induced glaucoma
iOP (mmhg)range
number of iOP-lowering medicationsrange
Visual acuity (logMar)range
10 (40)5 (20)1 (4)4 (16)3 (12)1 (4)1 (4)38.1 (10.3)22–624.1 (1.0)2–50.36 (0.31)0.05–1.0
Note: Data are presented as mean (sD) for continuous variables and number (%) for categorical variables.Abbreviations: MT, membrane tube; POag, primary open-angle glaucoma; iOP, intraocular pressure; logMar, logarithm of the minimum angle of resolution; sD, standard deviation.
Figure 2 Changes in iOP after the MT-type glaucoma shunt device implantation.Abbreviations: iOP, intraocular pressure; MT, membrane tube.
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glaucoma shunt device in West africans
Based on a cutoff value of #21 mmHg, complete success
rate was 96.0%, 50.0%, and 58.3% at postoperative 6, 12, and
24 months, respectively. Qualified success rate was 96.0%,
90.9%, and 83.3% at postoperative 6, 12, and 24 months,
respectively (Table 2). By using the survival analysis, the
cumulative survival rate (standard error) was 96.0% (3.9%),
89.0% (6.0%), and 81.3% (10.6%) at postoperative 6, 18, and
36 months, respectively (Figure 3). Three eyes were classified
as surgical failure at postoperative 6, 18, and 24 months. All
of these eyes were defined as failure because of high IOP.
The mean (SD) number of IOP-lowering medications
decreased from a preoperative value of 4.1 (1.0) to a post-
operative value of 0.6 (0.9) and 0.9 (1.1) at postoperative
1 and 2 years, respectively (P,0.01). There was no signifi-
cant change in visual acuity after the operation (P.0.05).
Postoperative complications included tube retraction at
postoperative 6 months in one case and a case of microbial
keratitis in a poorly controlled diabetic patient 3 months after
the operation. There were no other observed complications,
such as postoperative ocular hypotony, shallow anterior
chamber, choroidal effusion, hyphema, infection, occlusion
of tube, exposure of the device, eyelid problems, or ocular
motility disturbance. Two patients had encapsulated blebs
and underwent needling revision of the fibrous tissues around
the device at postoperative 4 and 6 months, respectively,
while another patient had progression of a preexisting corneal
decompensation. This patient had neovascular glaucoma
and had undergone three surgeries previously, including
360° transscleral cyclophotocoagulation for intractable
glaucoma before presentation at our clinic. This patient
subsequently underwent Descemet’s stripping automated
endothelial keratoplasty and at postoperative 3 years, still
had well-controlled IOP. When postoperative IOP, number of
IOP-lowering medication, and success rates were compared
between the eyes with previous trabeculectomy and eyes
without previous trabeculectomy, there was no significant
difference (P.0.05).
DiscussionThe most common glaucoma surgery in SSA remains trab-
eculectomy even though the African race is associated with a
higher failure rate of this surgery compared to Caucasians.8,9
Other glaucoma surgeries, such as GDD implantation, are
not commonly performed in much of SSA; there have been
only a few reports regarding the outcomes of GDD implanta-
tion in East Africans.16–18 This is mainly because of the high
cost of the devices and the need for patch graft materials,
such as scleral graft and pericardial tissue, which are often
not readily available in many parts of SSA. Therefore, it is
always a huge challenge for ophthalmologists in SSA to deal
with cases of failed trabeculectomies or refractory glaucoma,
which is expected to have a risk of surgical failure after
trabeculectomy.
According to our clinical experience, the Finetube MT
implantation showed a possibility of safe and effective
IOP control in West Africans with refractory glaucoma.
Furthermore, although it is not commercially available yet,
the Finetube MT can be made easily with simple materials
Table 2 success rate (%) after MT-type glaucoma shunt device implantation
Post-operative time
Complete success Qualified success
#21 mmHg #18 mmHg #15 mmHg #21 mmHg #18 mmHg #15 mmHg
6 months (n=25) 96.0 80.0 52.0 96.0 96.0 64.012 months (n=22) 50.0 45.5 40.9 90.9 86.4 59.118 months (n=18) 55.6 55.6 44.4 89.0 83.3 50.024 months (n=12) 58.3 58.3 41.7 83.3 83.3 58.3
Abbreviation: MT, membrane tube.
Figure 3 Kaplan–Meier survival curve after the MT-type glaucoma shunt device implantation.Note: Success was defined as an IOP between 6 and 21 mmHg and reduced by $20% from baseline, with or without the use of iOP-lowering medications.Abbreviations: MT, membrane tube; iOP, intraocular pressure.
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Olawoye et al
and the tubes do not need additional cover materials as they
are tunneled into the sclera. Therefore, we think that the
Finetube MT may be appropriate for resource-constrained
settings, such as in SAA.
The main indications for Finetube MT implantation in
our study were failed trabeculectomy with high IOP despite
maximum tolerable medical therapy and eyes with refrac-
tory glaucoma, such as neovascular and uveitic glaucoma.
Studies have demonstrated an increase in the use of GDDs
as an alternative to trabeculectomy, especially in eyes that
have undergone previous ocular surgery.14,15 More recently,
the indications for the GDDs have broadened and GDDs
are being considered as the first-line surgical treatment
option.22–24 In much of SSA, however, the low socioeconomic
status of many patients and the relatively high cost of these
devices make this difficult. The decision to use GDDs in the
current study was based on the results of the Trabeculec-
tomy versus Tube (TVT) study.22 The TVT study initially
showed similar outcomes between tube shunt surgery and
trabeculectomy with mitomycin-C (MMC) in the postopera-
tive 1 year; however, 5 years after the operation, patients
who underwent tube shunt surgery had a higher success rate
compared with those who underwent trabeculectomy with
MMC.22 Although the Finetube MT used in our study is
different from that used in the TVT study, we think that the
results may be similar because both devices have a similar
mechanism of aqueous drainage from the anterior chamber
to post-equatorial sub-Tenon’s space.
The results of the present study showed that the Finetube
MT implantation induced a 61.9%, 57.7%, and 61.4% reduc-
tion in IOP at postoperative 1, 2, and 3 years, respectively.
This is similar to the results of the previous study performed
with the Finetube MT in Korean patients.20 In terms of IOP
reduction, results of our study are also in line with results
of previous studies with conventional GDDs, such as AGV
and BGI.25–28 Regarding the surgical outcomes of GDD
implantation in indigenous Africans, Kiage et al16 in Kenya
showed that after AGV implantation, a mean preoperative
IOP of 36.4 mmHg reduced to 16.7 mmHg 2 months after
the operation. Giorgis18 in Ethiopia reported that a mean
preoperative IOP of 31.38 mmHg reduced to 17.15 mmHg
6 months after the operation. Although the follow-up dura-
tion in these studies was short, the results suggest that
GDDs may be promising in the surgical management of
glaucoma in SSA.
Given that the flow through the tube is most largely
affected by the tube diameter, postoperative ocular hypotony
is prevented in Finetube MT by using a smaller diameter
tube with an intraluminal stent. Compared to tubes of con-
ventional GDDs (AGV and BGI) that have an internal
diameter of 300 μm and an external diameter of ~600 μm,
the Finetube MT has an internal diameter of 200 μm and an
external diameter of 300 μm. Therefore, Finetube MT may
have less possibility of excessive aqueous drainage compared
to the tubes used in AGV or BGI.
Furthermore, the Finetube MT uses a tube with an intralu-
minal stent. This was purposed to prevent early postoperative
ocular hypotony and induce additional IOP reduction after
the operation by retracting the stent. In this study, no eye
showed postoperative ocular hypotony or hypotony-related
complications, such as shallow anterior chamber, choroidal
detachments, and effusions. In cases with early IOP rise,
stents were retracted or removed, and this induced effec-
tive additional IOP reduction. This can provide a controlled
stepwise reduction of IOP postoperatively by gradual retrac-
tion of the intraluminal stent; intraluminal stent retraction
of approximately half the length of the tube reduces IOP by
an additional 3–5 mmHg.19,20 Regardless of the IOP level,
all stents were completely removed by 1 month after the
operation. We hypothesized that at this time, subconjunctival
and episcleral tissue fibrosis would have developed, which
induces resistance to aqueous flow.20 Therefore, no ocular
hypotony may develop after the complete removal of the
intraluminal stent.
Other major complications of GDDs are mass effect of
device and corneal decompensation. In our study, no eye
showed mass effect-related complications, including tube
erosion or exposure, membrane exposure, eyelid problems,
and ocular motility disturbance. This may be attributable to
a smaller diameter of tube and a thinner and flexible aqueous
reservoir of Finetube MT compared to other GDDs, such as
BGI and AGV. Therefore, Finetube MT can be implanted in
eyes without sufficient subconjunctival space owing to thin-
ning or fibrosis of conjunctiva. When implanting Finetube
MT, no patch graft material is required. This would be an
important advantage in SSA where patch graft materials are
usually not available. In the present study, corneal decompen-
sation was found in only one eye that had previous multiple
ocular surgeries and had a low preoperative corneal endothe-
lial cell count prior to the surgery. We think that a smaller
tube may induce a lower risk of corneal decompensation.19,20
Further studies investigating the effect of tube diameter on
corneal endothelium are warranted.
GDD implantation is usually associated with less need for
postoperative follow-up compared to trabeculectomy, and the
TVT study revealed a decreased requirement for reoperation
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glaucoma shunt device in West africans
among eyes treated with GDDs compared to eyes treated with
trabeculectomy.22 By using Finetube MT, the most common
necessary postoperative intervention was stent retraction or
removal. We think that a relatively simple postoperative
management would be another advantage of Finetube MT,
especially in regions where patients have poor compliance
or regular postoperative follow-up is limited.
Based on our clinical experience, a tube with a smaller
diameter than conventional tubes showed similar IOP reduc-
tion with a lower prevalence of tube-related complications.19,20
However, we think that there still remains a possibility of
tube occlusion by inflammation materials, blood clots, or
silicone oil.
ConclusionWe have presented the clinical outcomes of Finetube MT
implantation to treat refractory glaucoma in the indigenous
West Africans. Although the sample size was not large and
follow-up period was not long, Finetube MT implantation
showed effective IOP control, with minimal risk of post-
operative ocular hypotony or tube-related complications.
We suggest that Finetube MT implantation may be a good
surgical option in the surgical management of refractory
glaucoma, especially in resource-constrained communities.
Further studies with a greater number of eyes and longer
period of follow-up are needed to further elucidate the effi-
cacy and safety of the Finetube MT in SSA.
DisclosureThe authors report no conflicts of interest in this work.
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